Is there parking there at hotel?
Is there a shuttle to the Target Field??
They had valet parking when it was the Graves, and I'm assuming they still do, but there is a pay lot across the street to park in if you don't want to pay for valet service.
There are buses and trains available that could take you to Target Field, though I'm not familiar with the routes. The front desk staff at the hotel should be knowledgeable about that.
Get an answer from Loews Minneapolis Hotel staff and past guests.